As for onboard information equipment (referred to as a head unit from now on), it can carry out besides navigation functions various video and audio processing providing rich entertainments for occupants in the car to have a pleasant time. In addition, it has become increasingly common to mount a plurality of AV (Audio Visual) devices in the vehicle for playing back video and audio sources. For this reason, DVDs become essential as a video playback source.
In a DVD drive, however, it sometimes occurs in a state in which power is not supplied that a working part such as a pickup or spindle slips out of a default position owing to vibration or impact peculiar to a vehicle. For this reason, it is necessary to perform initialization operation (correction to the default position) for ensuring of the DVD drive at its start.
The initialization operation mentioned above is usually managed by flags assigned to prescribed areas (flag areas) of a nonvolatile memory the foregoing head unit has. For example, as for a storage device (semiconductor memory, optical disk, or magnetic disk) requiring initialization, a storage device has been conventionally known which enables a host system (mobile terminal) to perform the initialization easily and which can prevent unnecessary rewriting of initialization information (see Patent Document 1, for example).